package com.lex.security.util;

import com.lex.common.redis.RedisService;
import io.jsonwebtoken.Claims;
import io.jsonwebtoken.Jwts;
import io.jsonwebtoken.SignatureAlgorithm;
import lombok.extern.slf4j.Slf4j;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.stereotype.Component;

import java.util.*;

/**
 * Created by lex on 2023/7/20
 * JwtTokenUtil工具类
 */
@Slf4j
@Component
public class JwtTokenUtil {
    private static final Logger LOGGER = LoggerFactory.getLogger(JwtTokenUtil.class);
    private static final String CLAIM_KEY_USERNAME = "sub";
    private static final String CLAIM_KEY_CREATED = "created";
    @Value("${jwt.secret}")
    private String secret;
    @Value("${jwt.expiration}")
    private Long expiration;
    @Value("${jwt.refresh_expiration}")
    private Long refresh_expiration;

    @Autowired
    private RedisService redisService;

    @Value("${redis.database}")
    private String REDIS_DATABASE;

    @Value("${redis.key-prefix}")
    private String REDIS_PREFIX;
    /**
     * 根据负载生成JWT的token
     */
    private String generateToken(Map<String,Object> claims){
        return Jwts.builder()
                .setClaims(claims)
                .setExpiration(generateExpirationDate())
                .signWith(SignatureAlgorithm.HS512,secret)
                .compact();
    }
    /**
     * 生成refreshToken
     */
    private String generateRefreshToken(Map<String,Object> claims) {
        return Jwts.builder()
                .setClaims(claims)
                .setExpiration(generateRefreshExpirationDate())
                .signWith(SignatureAlgorithm.HS512, secret)
                .compact();
    }
    /**
     * 从token中获取JWT中的负载
     */
    private Claims getClaimsFromToken(String token){
        Claims claims = null;
        try {
          claims = Jwts.parser()
                  .setSigningKey(secret)
                  .parseClaimsJws(token)
                  .getBody();
        } catch (Exception e) {
            LOGGER.info("JWT格式验证失败:{}", token);
        }
        return claims;
    }
    /**
     * 生成过期时间
     */
    private Date generateExpirationDate(){
        return new Date(System.currentTimeMillis() + expiration * 1000);
    }
    /**
     * 生成refreshToken过期时间
     */
    private Date generateRefreshExpirationDate(){
        return new Date(System.currentTimeMillis() + refresh_expiration * 1000);
    }
    /**
     * 从token中获取登录用户名
     */
    public String getUserNameFromToken(String token){
        String username;
        try {
            Claims claims = getClaimsFromToken(token);
            username = claims.getSubject();
        }catch (Exception e){
            username = null;
        }
        return username;
    }
    /**
     * 验证token是否还有效
     * @param token 客户端传入的token
     * @param userDetails 从数据库中查询出来的用户信息
     */
    public boolean validateToken(String token, UserDetails userDetails) {
        String key = REDIS_DATABASE + ":" + REDIS_PREFIX + ":" + "jwtBlackList";
        List<String> blackList =(List<String>) Optional.ofNullable(redisService.get(key)).orElse(new ArrayList<>());
        if (blackList.contains(token)){
            log.info("token已经被加入黑名单");
            return false;
        }
        String usernameFromToken = getUserNameFromToken(token);
        return usernameFromToken.equals(userDetails.getUsername()) && !isTokenExpired(token);
    }
    /**
     * 判断token是否已经失效
     */
    private boolean isTokenExpired(String token) {
        Date expiredDate = getExpiredDateFromToken(token);
        log.error("token过期时间"+expiredDate.toString());
        return expiredDate.before(new Date());
    }
    /**
     * 从token中获取过期时间
     */
    private Date getExpiredDateFromToken(String token) {
        Claims claims = getClaimsFromToken(token);
        return claims.getExpiration();
    }
    /**
     * 根据用户信息生成token
     */
    public String generateToken(UserDetails userDetails) {
        Map<String, Object> claims = new HashMap<>();
        claims.put(CLAIM_KEY_USERNAME, userDetails.getUsername());
        claims.put(CLAIM_KEY_CREATED, new Date());
        return generateToken(claims);
    }
    /**
     * 根据用户信息生成refreshToken
     */
    public String generateRefreshToken(UserDetails userDetails) {
        Map<String, Object> claims = new HashMap<>();
        claims.put(CLAIM_KEY_USERNAME, userDetails.getUsername());
        claims.put(CLAIM_KEY_CREATED, new Date());
        return generateRefreshToken(claims);
    }
    /**
     * 获取refresh_token的过期时间
     *
     */
    public Long getRefreshExpiredDateFromToken(String token) {
        Claims claims = getClaimsFromToken(token);
        Date expireDate =  claims.getExpiration();
        return expireDate.getTime();
    }
    /**
     * 判断token是否可以被刷新
     */
    public boolean canRefresh(String token) {
        return !isTokenExpired(token);
    }
    /**
     * 刷新token
     */
    public String refreshToken(String token) {
        Claims claims = getClaimsFromToken(token);
        claims.put(CLAIM_KEY_CREATED, new Date());
        return generateToken(claims);
    }

}
